Add software renderer implementation
parent
37f78fc1cc
commit
3ee511d71c
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@ -33,6 +33,7 @@
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#include "SDL_drawline.h"
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#include "SDL_drawpoint.h"
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#include "SDL_rotate.h"
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#include "SDL_triangle.h"
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/* SDL surface based renderer implementation */
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@ -560,6 +561,71 @@ SW_RenderCopyEx(SDL_Renderer * renderer, SDL_Surface *surface, SDL_Texture * tex
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return retval;
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}
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typedef struct GeometryFillData
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{
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SDL_Point dst;
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SDL_Color color;
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} GeometryFillData;
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typedef struct GeometryCopyData
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{
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SDL_Point src;
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SDL_Point dst;
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SDL_Color color;
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} GeometryCopyData;
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static int
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SW_QueueGeometry(SDL_Renderer *renderer, SDL_RenderCommand *cmd, SDL_Texture *texture,
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SDL_Vertex *vertices, int num_vertices, int *indices, int num_indices, float scale_x, float scale_y)
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{
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int i;
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int count = indices ? num_indices : num_vertices;
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void *verts;
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int sz = texture ? sizeof (GeometryCopyData) : sizeof (GeometryFillData);
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verts = (void *) SDL_AllocateRenderVertices(renderer, count * sz, 0, &cmd->data.draw.first);
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if (!verts) {
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return -1;
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}
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cmd->data.draw.count = count;
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if (texture) {
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GeometryCopyData *ptr = (GeometryCopyData *) verts;
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for (i = 0; i < count; i++) {
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SDL_Vertex *v = &vertices[indices ? indices[i] : i];
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ptr->src.x = v->tex_coord.x;
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ptr->src.y = v->tex_coord.y;
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ptr->dst.x = v->position.x * scale_x + renderer->viewport.x;
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ptr->dst.y = v->position.y * scale_y + renderer->viewport.y;
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trianglepoint_2_fixedpoint(&ptr->dst);
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ptr->color = v->color;
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ptr++;
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}
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} else {
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GeometryFillData *ptr = (GeometryFillData *) verts;
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for (i = 0; i < count; i++) {
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SDL_Vertex *v = &vertices[indices ? indices[i] : i];
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ptr->dst.x = v->position.x * scale_x + renderer->viewport.x;
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ptr->dst.y = v->position.y * scale_y + renderer->viewport.y;
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trianglepoint_2_fixedpoint(&ptr->dst);
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ptr->color = v->color;
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ptr++;
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}
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}
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return 0;
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}
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static void
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PrepTextureForCopy(const SDL_RenderCommand *cmd)
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{
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@ -734,6 +800,39 @@ SW_RunCommandQueue(SDL_Renderer * renderer, SDL_RenderCommand *cmd, void *vertic
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break;
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}
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case SDL_RENDERCMD_GEOMETRY: {
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int i;
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SDL_Rect *verts = (SDL_Rect *) (((Uint8 *) vertices) + cmd->data.draw.first);
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const int count = (int) cmd->data.draw.count;
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SDL_Texture *texture = cmd->data.draw.texture;
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const SDL_BlendMode blend = cmd->data.draw.blend;
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SetDrawState(surface, &drawstate);
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if (texture) {
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SDL_Surface *src = (SDL_Surface *) texture->driverdata;
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GeometryCopyData *ptr = (GeometryCopyData *) verts;
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PrepTextureForCopy(cmd);
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for (i = 0; i < count; i += 3, ptr += 3) {
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SDL_SW_BlitTriangle(
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src,
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&(ptr[0].src), &(ptr[1].src), &(ptr[2].src),
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surface,
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&(ptr[0].dst), &(ptr[1].dst), &(ptr[2].dst),
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ptr[0].color, ptr[1].color, ptr[2].color);
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}
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} else {
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GeometryFillData *ptr = (GeometryFillData *) verts;
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for (i = 0; i < count; i += 3, ptr += 3) {
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SDL_SW_FillTriangle(surface, &(ptr[0].dst), &(ptr[1].dst), &(ptr[2].dst), blend, ptr[0].color, ptr[1].color, ptr[2].color);
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}
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}
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break;
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}
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case SDL_RENDERCMD_NO_OP:
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break;
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}
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@ -843,6 +942,7 @@ SW_CreateRendererForSurface(SDL_Surface * surface)
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renderer->QueueFillRects = SW_QueueFillRects;
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renderer->QueueCopy = SW_QueueCopy;
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renderer->QueueCopyEx = SW_QueueCopyEx;
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renderer->QueueGeometry = SW_QueueGeometry;
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renderer->RunCommandQueue = SW_RunCommandQueue;
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renderer->RenderReadPixels = SW_RenderReadPixels;
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renderer->RenderPresent = SW_RenderPresent;
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@ -0,0 +1,827 @@
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/*
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Simple DirectMedia Layer
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Copyright (C) 1997-2021 Sam Lantinga <slouken@libsdl.org>
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This software is provided 'as-is', without any express or implied
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warranty. In no event will the authors be held liable for any damages
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arising from the use of this software.
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Permission is granted to anyone to use this software for any purpose,
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including commercial applications, and to alter it and redistribute it
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freely, subject to the following restrictions:
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1. The origin of this software must not be misrepresented; you must not
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claim that you wrote the original software. If you use this software
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in a product, an acknowledgment in the product documentation would be
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appreciated but is not required.
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2. Altered source versions must be plainly marked as such, and must not be
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misrepresented as being the original software.
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3. This notice may not be removed or altered from any source distribution.
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*/
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#include "../../SDL_internal.h"
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#if SDL_VIDEO_RENDER_SW && !SDL_RENDER_DISABLED
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#include "SDL_surface.h"
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#include "SDL_triangle.h"
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#include "../../video/SDL_blit.h"
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/* fixed points bits precision
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* Set to 1, so that it can start rendering wth middle of a pixel precision.
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* It doesn't need to be increased.
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* But, if increased too much, it overflows (srcx, srcy) coordinates used for filling with texture.
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* (which could be turned to int64).
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*/
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#define FP_BITS 1
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#define COLOR_EQ(c1, c2) ((c1).r == (c2).r && (c1).g == (c2).g && (c1).b == (c2).b && (c1).a == (c2).a)
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static void SDL_BlitTriangle_Slow(SDL_BlitInfo * info,
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SDL_Point s2_x_area, SDL_Rect dstrect, int area, int bias_w0, int bias_w1, int bias_w2,
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int d2d1_y, int d1d2_x, int d0d2_y, int d2d0_x, int d1d0_y, int d0d1_x,
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int s2s0_x, int s2s1_x, int s2s0_y, int s2s1_y, int w0_row, int w1_row, int w2_row,
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SDL_Color c0, SDL_Color c1, SDL_Color c2, int is_uniform);
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#if 0
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int SDL_BlitTriangle(SDL_Surface *src, const SDL_Point srcpoints[3], SDL_Surface *dst, const SDL_Point dstpoints[3])
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{
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int i;
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SDL_Point points[6];
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if (src == NULL || dst == NULL) {
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return -1;
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}
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for (i = 0; i < 3; i++) {
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if (srcpoints[i].x < 0 || srcpoints[i].y < 0 || srcpoints[i].x >= src->w || srcpoints[i].y >= src->h) {
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return SDL_SetError("Values of 'srcpoints' out of bounds");
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}
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}
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points[0] = srcpoints[0];
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points[1] = dstpoints[0];
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points[2] = srcpoints[1];
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points[3] = dstpoints[1];
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points[4] = srcpoints[2];
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points[5] = dstpoints[2];
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for (i = 0; i < 3; i++) {
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trianglepoint_2_fixedpoint(&points[2 * i + 1]);
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}
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return SDL_SW_BlitTriangle(src, dst, points);
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}
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int SDL_FillTriangle(SDL_Surface *dst, const SDL_Point points[3], Uint32 color)
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{
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int i;
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SDL_Point points_tmp[3];
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if (dst == NULL) {
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return -1;
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}
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for (i = 0; i < 3; i++) {
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points_tmp[i] = points[i];
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trianglepoint_2_fixedpoint(&points_tmp[i]);
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}
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return SDL_SW_FillTriangle(dst, points_tmp, SDL_BLENDMODE_NONE, color);
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}
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#endif
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/* cross product AB x AC */
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static float cross_product(const SDL_Point *a, const SDL_Point *b, int c_x, int c_y)
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{
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return (b->x - a->x) * (c_y - a->y) - (b->y - a->y) * (c_x - a->x);
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}
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/* check for top left rules */
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static int is_top_left(const SDL_Point *a, const SDL_Point *b, int is_clockwise)
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{
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if (is_clockwise) {
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if (a->y == b->y && a->x < b->x) {
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return 1;
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}
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if (b->y < a->y) {
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return 1;
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}
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} else {
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if (a->y == b->y && b->x < a->x) {
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return 1;
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}
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if (a->y < b->y) {
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return 1;
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}
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}
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return 0;
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}
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void trianglepoint_2_fixedpoint(SDL_Point *a) {
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a->x <<= FP_BITS;
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a->y <<= FP_BITS;
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}
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/* bounding rect of three points */
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static void bounding_rect(const SDL_Point *a, const SDL_Point *b, const SDL_Point *c, SDL_Rect *r)
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{
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int min_x = SDL_min(a->x, SDL_min(b->x, c->x));
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int max_x = SDL_max(a->x, SDL_max(b->x, c->x));
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int min_y = SDL_min(a->y, SDL_min(b->y, c->y));
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int max_y = SDL_max(a->y, SDL_max(b->y, c->y));
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/* points are in fixed point, shift back */
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r->x = min_x >> FP_BITS;
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r->y = min_y >> FP_BITS;
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r->w = (max_x - min_x) >> FP_BITS;
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r->h = (max_y - min_y) >> FP_BITS;
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}
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/* Triangle rendering, using Barycentric coordinates (w0, w1, w2)
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*
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* The cross product isn't computed from scratch at each iteration,
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* but optimized using constant step increments
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*
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*/
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#define TRIANGLE_BEGIN_LOOP \
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{ \
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int x, y; \
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for (y = 0; y < dstrect.h; y++) { \
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/* y start */ \
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int w0 = w0_row; \
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int w1 = w1_row; \
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int w2 = w2_row; \
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for (x = 0; x < dstrect.w; x++) { \
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/* In triangle */ \
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if (w0 + bias_w0 >= 0 && w1 + bias_w1 >= 0 && w2 + bias_w2 >= 0) { \
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Uint8 *dptr = (Uint8 *) dst_ptr + x * dstbpp; \
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#define TRIANGLE_GET_TEXTCOORD \
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int srcx = (w0 * s2s0_x + w1 * s2s1_x + s2_x_area.x) / area; \
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int srcy = (w0 * s2s0_y + w1 * s2s1_y + s2_x_area.y) / area; \
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#define TRIANGLE_GET_MAPPED_COLOR \
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int r = (w0 * c0.r + w1 * c1.r + w2 * c2.r) / area; \
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int g = (w0 * c0.g + w1 * c1.g + w2 * c2.g) / area; \
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int b = (w0 * c0.b + w1 * c1.b + w2 * c2.b) / area; \
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int a = (w0 * c0.a + w1 * c1.a + w2 * c2.a) / area; \
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int color = SDL_MapRGBA(format, r, g, b, a); \
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#define TRIANGLE_GET_COLOR \
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int r = (w0 * c0.r + w1 * c1.r + w2 * c2.r) / area; \
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int g = (w0 * c0.g + w1 * c1.g + w2 * c2.g) / area; \
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int b = (w0 * c0.b + w1 * c1.b + w2 * c2.b) / area; \
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int a = (w0 * c0.a + w1 * c1.a + w2 * c2.a) / area; \
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#define TRIANGLE_END_LOOP \
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} \
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/* x += 1 */ \
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w0 += d2d1_y; \
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w1 += d0d2_y; \
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w2 += d1d0_y; \
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} \
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/* y += 1 */ \
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w0_row += d1d2_x; \
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w1_row += d2d0_x; \
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w2_row += d0d1_x; \
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dst_ptr += dst_pitch; \
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} \
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} \
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int SDL_SW_FillTriangle(SDL_Surface *dst, SDL_Point *d0, SDL_Point *d1, SDL_Point *d2, SDL_BlendMode blend, SDL_Color c0, SDL_Color c1, SDL_Color c2)
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{
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int ret = 0;
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int dst_locked = 0;
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SDL_Rect dstrect;
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int dstbpp;
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Uint8 *dst_ptr;
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int dst_pitch;
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int area, is_clockwise;
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int d2d1_y, d1d2_x, d0d2_y, d2d0_x, d1d0_y, d0d1_x;
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int w0_row, w1_row, w2_row;
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int bias_w0, bias_w1, bias_w2;
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int is_uniform;
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SDL_Surface *tmp = NULL;
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if (dst == NULL) {
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return -1;
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}
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area = cross_product(d0, d1, d2->x, d2->y);
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is_uniform = COLOR_EQ(c0, c1) && COLOR_EQ(c1, c2);
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/* Flat triangle */
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if (area == 0) {
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return 0;
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}
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/* Lock the destination, if needed */
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if (SDL_MUSTLOCK(dst)) {
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if (SDL_LockSurface(dst) < 0) {
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ret = -1;
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goto end;
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} else {
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dst_locked = 1;
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}
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}
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bounding_rect(d0, d1, d2, &dstrect);
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{
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/* Clip triangle rect with surface rect */
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SDL_Rect rect;
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rect.x = 0;
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rect.y = 0;
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rect.w = dst->w;
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rect.h = dst->h;
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SDL_IntersectRect(&dstrect, &rect, &dstrect);
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}
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{
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/* Clip triangle with surface clip rect */
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SDL_Rect rect;
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SDL_GetClipRect(dst, &rect);
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SDL_IntersectRect(&dstrect, &rect, &dstrect);
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}
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if (blend != SDL_BLENDMODE_NONE) {
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int format = dst->format->format;
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/* need an alpha format */
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if (! dst->format->Amask) {
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format = SDL_PIXELFORMAT_ARGB8888;
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}
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/* Use an intermediate surface */
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tmp = SDL_CreateRGBSurfaceWithFormat(0, dstrect.w, dstrect.h, 0, format);
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if (tmp == NULL) {
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ret = -1;
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goto end;
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}
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if (blend == SDL_BLENDMODE_MOD) {
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Uint32 c = SDL_MapRGBA(tmp->format, 255, 255, 255, 255);
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SDL_FillRect(tmp, NULL, c);
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}
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SDL_SetSurfaceBlendMode(tmp, blend);
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dstbpp = tmp->format->BytesPerPixel;
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dst_ptr = tmp->pixels;
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dst_pitch = tmp->pitch;
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} else {
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/* Write directly to destination surface */
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dstbpp = dst->format->BytesPerPixel;
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dst_ptr = (Uint8 *)dst->pixels + dstrect.x * dstbpp + dstrect.y * dst->pitch;
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dst_pitch = dst->pitch;
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}
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is_clockwise = area > 0;
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area = SDL_abs(area);
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d2d1_y = (d1->y - d2->y) << FP_BITS;
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d0d2_y = (d2->y - d0->y) << FP_BITS;
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d1d0_y = (d0->y - d1->y) << FP_BITS;
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d1d2_x = (d2->x - d1->x) << FP_BITS;
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d2d0_x = (d0->x - d2->x) << FP_BITS;
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d0d1_x = (d1->x - d0->x) << FP_BITS;
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/* Starting point for rendering, at the middle of a pixel */
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{
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SDL_Point p;
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p.x = dstrect.x;
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p.y = dstrect.y;
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trianglepoint_2_fixedpoint(&p);
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p.x += (1 << FP_BITS) / 2;
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p.y += (1 << FP_BITS) / 2;
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w0_row = cross_product(d1, d2, p.x, p.y);
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w1_row = cross_product(d2, d0, p.x, p.y);
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w2_row = cross_product(d0, d1, p.x, p.y);
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}
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/* Handle anti-clockwise triangles */
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if (! is_clockwise) {
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d2d1_y *= -1;
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d0d2_y *= -1;
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d1d0_y *= -1;
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d1d2_x *= -1;
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d2d0_x *= -1;
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d0d1_x *= -1;
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w0_row *= -1;
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w1_row *= -1;
|
||||
w2_row *= -1;
|
||||
}
|
||||
|
||||
/* Add a bias to respect top-left rasterization rule */
|
||||
bias_w0 = (is_top_left(d1, d2, is_clockwise) ? 0 : -1);
|
||||
bias_w1 = (is_top_left(d2, d0, is_clockwise) ? 0 : -1);
|
||||
bias_w2 = (is_top_left(d0, d1, is_clockwise) ? 0 : -1);
|
||||
|
||||
if (is_uniform) {
|
||||
Uint32 color;
|
||||
if (tmp) {
|
||||
if (dst->format->Amask) {
|
||||
color = SDL_MapRGBA(tmp->format, c0.r, c0.g, c0.b, c0.a);
|
||||
} else {
|
||||
//color = SDL_MapRGB(tmp->format, c0.r, c0.g, c0.b);
|
||||
color = SDL_MapRGBA(tmp->format, c0.r, c0.g, c0.b, c0.a);
|
||||
}
|
||||
} else {
|
||||
color = SDL_MapRGBA(dst->format, c0.r, c0.g, c0.b, c0.a);
|
||||
}
|
||||
|
||||
if (dstbpp == 4) {
|
||||
TRIANGLE_BEGIN_LOOP
|
||||
{
|
||||
*(Uint32 *)dptr = color;
|
||||
}
|
||||
TRIANGLE_END_LOOP
|
||||
} else if (dstbpp == 3) {
|
||||
TRIANGLE_BEGIN_LOOP
|
||||
{
|
||||
Uint8 *s = (Uint8*)&color;
|
||||
dptr[0] = s[0];
|
||||
dptr[1] = s[1];
|
||||
dptr[2] = s[2];
|
||||
}
|
||||
TRIANGLE_END_LOOP
|
||||
} else if (dstbpp == 2) {
|
||||
TRIANGLE_BEGIN_LOOP
|
||||
{
|
||||
*(Uint16 *)dptr = color;
|
||||
}
|
||||
TRIANGLE_END_LOOP
|
||||
} else if (dstbpp == 1) {
|
||||
TRIANGLE_BEGIN_LOOP
|
||||
{
|
||||
*dptr = color;
|
||||
}
|
||||
TRIANGLE_END_LOOP
|
||||
}
|
||||
} else {
|
||||
SDL_PixelFormat *format = dst->format;
|
||||
if (tmp) {
|
||||
format = tmp->format;
|
||||
}
|
||||
if (dstbpp == 4) {
|
||||
TRIANGLE_BEGIN_LOOP
|
||||
{
|
||||
TRIANGLE_GET_MAPPED_COLOR
|
||||
*(Uint32 *)dptr = color;
|
||||
}
|
||||
TRIANGLE_END_LOOP
|
||||
} else if (dstbpp == 3) {
|
||||
TRIANGLE_BEGIN_LOOP
|
||||
{
|
||||
TRIANGLE_GET_MAPPED_COLOR
|
||||
Uint8 *s = (Uint8*)&color;
|
||||
dptr[0] = s[0];
|
||||
dptr[1] = s[1];
|
||||
dptr[2] = s[2];
|
||||
}
|
||||
TRIANGLE_END_LOOP
|
||||
} else if (dstbpp == 2) {
|
||||
TRIANGLE_BEGIN_LOOP
|
||||
{
|
||||
TRIANGLE_GET_MAPPED_COLOR
|
||||
*(Uint16 *)dptr = color;
|
||||
}
|
||||
TRIANGLE_END_LOOP
|
||||
} else if (dstbpp == 1) {
|
||||
TRIANGLE_BEGIN_LOOP
|
||||
{
|
||||
TRIANGLE_GET_MAPPED_COLOR
|
||||
*dptr = color;
|
||||
}
|
||||
TRIANGLE_END_LOOP
|
||||
}
|
||||
}
|
||||
|
||||
if (tmp) {
|
||||
SDL_BlitSurface(tmp, NULL, dst, &dstrect);
|
||||
SDL_FreeSurface(tmp);
|
||||
}
|
||||
|
||||
end:
|
||||
if (dst_locked) {
|
||||
SDL_UnlockSurface(dst);
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
int SDL_SW_BlitTriangle(
|
||||
SDL_Surface *src,
|
||||
SDL_Point *s0, SDL_Point *s1, SDL_Point *s2,
|
||||
SDL_Surface *dst,
|
||||
SDL_Point *d0, SDL_Point *d1, SDL_Point *d2,
|
||||
SDL_Color c0, SDL_Color c1, SDL_Color c2)
|
||||
{
|
||||
int ret = 0;
|
||||
int src_locked = 0;
|
||||
int dst_locked = 0;
|
||||
|
||||
SDL_BlendMode blend;
|
||||
|
||||
SDL_Rect srcrect;
|
||||
SDL_Rect dstrect;
|
||||
|
||||
SDL_Point s2_x_area;
|
||||
|
||||
int dstbpp;
|
||||
Uint8 *dst_ptr;
|
||||
int dst_pitch;
|
||||
|
||||
int *src_ptr;
|
||||
int src_pitch;
|
||||
|
||||
int area, is_clockwise;
|
||||
|
||||
int d2d1_y, d1d2_x, d0d2_y, d2d0_x, d1d0_y, d0d1_x;
|
||||
int s2s0_x, s2s1_x, s2s0_y, s2s1_y;
|
||||
|
||||
int w0_row, w1_row, w2_row;
|
||||
int bias_w0, bias_w1, bias_w2;
|
||||
|
||||
int is_uniform;
|
||||
|
||||
int has_modulation;
|
||||
|
||||
if (src == NULL || dst == NULL) {
|
||||
return -1;
|
||||
}
|
||||
|
||||
area = cross_product(d0, d1, d2->x, d2->y);
|
||||
|
||||
/* Flat triangle */
|
||||
if (area == 0) {
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Lock the destination, if needed */
|
||||
if (SDL_MUSTLOCK(dst)) {
|
||||
if (SDL_LockSurface(dst) < 0) {
|
||||
ret = -1;
|
||||
goto end;
|
||||
} else {
|
||||
dst_locked = 1;
|
||||
}
|
||||
}
|
||||
|
||||
/* Lock the source, if needed */
|
||||
if (SDL_MUSTLOCK(src)) {
|
||||
if (SDL_LockSurface(src) < 0) {
|
||||
ret = -1;
|
||||
goto end;
|
||||
} else {
|
||||
src_locked = 1;
|
||||
}
|
||||
}
|
||||
|
||||
is_uniform = COLOR_EQ(c0, c1) && COLOR_EQ(c1, c2);
|
||||
|
||||
bounding_rect(s0, s1, s2, &srcrect);
|
||||
bounding_rect(d0, d1, d2, &dstrect);
|
||||
|
||||
SDL_GetSurfaceBlendMode(src, &blend);
|
||||
|
||||
if (is_uniform) {
|
||||
// SDL_GetSurfaceColorMod(src, &r, &g, &b);
|
||||
has_modulation = c0.r != 255 || c0.g != 255 || c0.b != 255 || c0.a != 255;;
|
||||
} else {
|
||||
has_modulation = SDL_TRUE;
|
||||
}
|
||||
|
||||
{
|
||||
/* Clip triangle rect with surface rect */
|
||||
SDL_Rect rect;
|
||||
rect.x = 0;
|
||||
rect.y = 0;
|
||||
rect.w = dst->w;
|
||||
rect.h = dst->h;
|
||||
|
||||
SDL_IntersectRect(&dstrect, &rect, &dstrect);
|
||||
}
|
||||
|
||||
{
|
||||
/* Clip triangle with surface clip rect */
|
||||
SDL_Rect rect;
|
||||
SDL_GetClipRect(dst, &rect);
|
||||
SDL_IntersectRect(&dstrect, &rect, &dstrect);
|
||||
}
|
||||
|
||||
/* Set destination pointer */
|
||||
dstbpp = dst->format->BytesPerPixel;
|
||||
dst_ptr = (Uint8 *)dst->pixels + dstrect.x * dstbpp + dstrect.y * dst->pitch;
|
||||
dst_pitch = dst->pitch;
|
||||
|
||||
/* Set source pointer */
|
||||
src_ptr = src->pixels;
|
||||
src_pitch = src->pitch;
|
||||
|
||||
is_clockwise = area > 0;
|
||||
area = SDL_abs(area);
|
||||
|
||||
d2d1_y = (d1->y - d2->y) << FP_BITS;
|
||||
d0d2_y = (d2->y - d0->y) << FP_BITS;
|
||||
d1d0_y = (d0->y - d1->y) << FP_BITS;
|
||||
|
||||
|
||||
d1d2_x = (d2->x - d1->x) << FP_BITS;
|
||||
d2d0_x = (d0->x - d2->x) << FP_BITS;
|
||||
d0d1_x = (d1->x - d0->x) << FP_BITS;
|
||||
|
||||
s2s0_x = s0->x - s2->x;
|
||||
s2s1_x = s1->x - s2->x;
|
||||
s2s0_y = s0->y - s2->y;
|
||||
s2s1_y = s1->y - s2->y;
|
||||
|
||||
/* Starting point for rendering, at the middle of a pixel */
|
||||
{
|
||||
SDL_Point p;
|
||||
p.x = dstrect.x;
|
||||
p.y = dstrect.y;
|
||||
trianglepoint_2_fixedpoint(&p);
|
||||
p.x += (1 << FP_BITS) / 2;
|
||||
p.y += (1 << FP_BITS) / 2;
|
||||
w0_row = cross_product(d1, d2, p.x, p.y);
|
||||
w1_row = cross_product(d2, d0, p.x, p.y);
|
||||
w2_row = cross_product(d0, d1, p.x, p.y);
|
||||
}
|
||||
|
||||
/* Handle anti-clockwise triangles */
|
||||
if (! is_clockwise) {
|
||||
d2d1_y *= -1;
|
||||
d0d2_y *= -1;
|
||||
d1d0_y *= -1;
|
||||
d1d2_x *= -1;
|
||||
d2d0_x *= -1;
|
||||
d0d1_x *= -1;
|
||||
w0_row *= -1;
|
||||
w1_row *= -1;
|
||||
w2_row *= -1;
|
||||
}
|
||||
|
||||
/* Add a bias to respect top-left rasterization rule */
|
||||
bias_w0 = (is_top_left(d1, d2, is_clockwise) ? 0 : -1);
|
||||
bias_w1 = (is_top_left(d2, d0, is_clockwise) ? 0 : -1);
|
||||
bias_w2 = (is_top_left(d0, d1, is_clockwise) ? 0 : -1);
|
||||
|
||||
/* precompute constant 's2->x * area' used in TRIANGLE_GET_TEXTCOORD */
|
||||
s2_x_area.x = s2->x * area;
|
||||
s2_x_area.y = s2->y * area;
|
||||
|
||||
if (blend != SDL_BLENDMODE_NONE || src->format->format != dst->format->format || has_modulation || ! is_uniform) {
|
||||
/* Use SDL_BlitTriangle_Slow */
|
||||
|
||||
SDL_BlitInfo *info = &src->map->info;
|
||||
SDL_BlitInfo tmp_info;
|
||||
|
||||
SDL_zero(tmp_info);
|
||||
|
||||
tmp_info.src_fmt = src->format;
|
||||
tmp_info.dst_fmt = dst->format;
|
||||
tmp_info.flags = info->flags;
|
||||
/*
|
||||
tmp_info.r = info->r;
|
||||
tmp_info.g = info->g;
|
||||
tmp_info.b = info->b;
|
||||
tmp_info.a = info->a;
|
||||
*/
|
||||
tmp_info.r = c0.r;
|
||||
tmp_info.g = c0.g;
|
||||
tmp_info.b = c0.b;
|
||||
tmp_info.a = c0.a;
|
||||
|
||||
|
||||
tmp_info.flags &= ~(SDL_COPY_MODULATE_COLOR | SDL_COPY_MODULATE_ALPHA);
|
||||
|
||||
if (c0.r != 255 || c1.r != 255 || c2.r != 255 ||
|
||||
c0.g != 255 || c1.g != 255 || c2.g != 255 ||
|
||||
c0.b != 255 || c1.b != 255 || c2.b != 255) {
|
||||
tmp_info.flags |= SDL_COPY_MODULATE_COLOR;
|
||||
}
|
||||
|
||||
if (c0.a != 255 || c1.a != 255 || c2.a != 255) {
|
||||
tmp_info.flags |= SDL_COPY_MODULATE_ALPHA;
|
||||
}
|
||||
|
||||
tmp_info.colorkey = info->colorkey;
|
||||
|
||||
/* src */
|
||||
tmp_info.src = (Uint8 *) src_ptr;
|
||||
tmp_info.src_pitch = src_pitch;
|
||||
|
||||
/* dst */
|
||||
tmp_info.dst = (Uint8 *) dst_ptr;
|
||||
tmp_info.dst_pitch = dst_pitch;
|
||||
|
||||
SDL_BlitTriangle_Slow(&tmp_info, s2_x_area, dstrect, area, bias_w0, bias_w1, bias_w2,
|
||||
d2d1_y, d1d2_x, d0d2_y, d2d0_x, d1d0_y, d0d1_x,
|
||||
s2s0_x, s2s1_x, s2s0_y, s2s1_y, w0_row, w1_row, w2_row,
|
||||
c0, c1, c2, is_uniform);
|
||||
|
||||
goto end;
|
||||
}
|
||||
|
||||
if (dstbpp == 4) {
|
||||
TRIANGLE_BEGIN_LOOP
|
||||
{
|
||||
TRIANGLE_GET_TEXTCOORD
|
||||
Uint32 *sptr = (Uint32 *)((Uint8 *) src_ptr + srcy * src_pitch);
|
||||
*(Uint32 *)dptr = sptr[srcx];
|
||||
}
|
||||
TRIANGLE_END_LOOP
|
||||
} else if (dstbpp == 3) {
|
||||
TRIANGLE_BEGIN_LOOP
|
||||
{
|
||||
TRIANGLE_GET_TEXTCOORD
|
||||
Uint8 *sptr = (Uint8 *)((Uint8 *) src_ptr + srcy * src_pitch);
|
||||
dptr[0] = sptr[3 * srcx];
|
||||
dptr[1] = sptr[3 * srcx + 1];
|
||||
dptr[2] = sptr[3 * srcx + 2];
|
||||
}
|
||||
TRIANGLE_END_LOOP
|
||||
} else if (dstbpp == 2) {
|
||||
TRIANGLE_BEGIN_LOOP
|
||||
{
|
||||
TRIANGLE_GET_TEXTCOORD
|
||||
Uint16 *sptr = (Uint16 *)((Uint8 *) src_ptr + srcy * src_pitch);
|
||||
*(Uint16 *)dptr = sptr[srcx];
|
||||
}
|
||||
TRIANGLE_END_LOOP
|
||||
} else if (dstbpp == 1) {
|
||||
TRIANGLE_BEGIN_LOOP
|
||||
{
|
||||
TRIANGLE_GET_TEXTCOORD
|
||||
Uint8 *sptr = (Uint8 *)((Uint8 *) src_ptr + srcy * src_pitch);
|
||||
*dptr = sptr[srcx];
|
||||
}
|
||||
TRIANGLE_END_LOOP
|
||||
}
|
||||
|
||||
end:
|
||||
if (dst_locked) {
|
||||
SDL_UnlockSurface(dst);
|
||||
}
|
||||
if (src_locked) {
|
||||
SDL_UnlockSurface(src);
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
|
||||
static void
|
||||
SDL_BlitTriangle_Slow(SDL_BlitInfo *info,
|
||||
SDL_Point s2_x_area, SDL_Rect dstrect, int area, int bias_w0, int bias_w1, int bias_w2,
|
||||
int d2d1_y, int d1d2_x, int d0d2_y, int d2d0_x, int d1d0_y, int d0d1_x,
|
||||
int s2s0_x, int s2s1_x, int s2s0_y, int s2s1_y, int w0_row, int w1_row, int w2_row,
|
||||
SDL_Color c0, SDL_Color c1, SDL_Color c2, int is_uniform)
|
||||
{
|
||||
const int flags = info->flags;
|
||||
Uint32 modulateR = info->r;
|
||||
Uint32 modulateG = info->g;
|
||||
Uint32 modulateB = info->b;
|
||||
Uint32 modulateA = info->a;
|
||||
Uint32 srcpixel;
|
||||
Uint32 srcR, srcG, srcB, srcA;
|
||||
Uint32 dstpixel;
|
||||
Uint32 dstR, dstG, dstB, dstA;
|
||||
SDL_PixelFormat *src_fmt = info->src_fmt;
|
||||
SDL_PixelFormat *dst_fmt = info->dst_fmt;
|
||||
int srcbpp = src_fmt->BytesPerPixel;
|
||||
int dstbpp = dst_fmt->BytesPerPixel;
|
||||
Uint32 rgbmask = ~src_fmt->Amask;
|
||||
Uint32 ckey = info->colorkey & rgbmask;
|
||||
|
||||
Uint8 *dst_ptr = info->dst;
|
||||
int dst_pitch = info->dst_pitch;;
|
||||
|
||||
TRIANGLE_BEGIN_LOOP
|
||||
{
|
||||
Uint8 *src;
|
||||
Uint8 *dst = dptr;
|
||||
TRIANGLE_GET_TEXTCOORD
|
||||
src = (info->src + (srcy * info->src_pitch) + (srcx * srcbpp));
|
||||
if (src_fmt->Amask) {
|
||||
DISEMBLE_RGBA(src, srcbpp, src_fmt, srcpixel, srcR, srcG,
|
||||
srcB, srcA);
|
||||
} else {
|
||||
DISEMBLE_RGB(src, srcbpp, src_fmt, srcpixel, srcR, srcG,
|
||||
srcB);
|
||||
srcA = 0xFF;
|
||||
}
|
||||
if (flags & SDL_COPY_COLORKEY) {
|
||||
/* srcpixel isn't set for 24 bpp */
|
||||
if (srcbpp == 3) {
|
||||
srcpixel = (srcR << src_fmt->Rshift) |
|
||||
(srcG << src_fmt->Gshift) | (srcB << src_fmt->Bshift);
|
||||
}
|
||||
if ((srcpixel & rgbmask) == ckey) {
|
||||
continue;
|
||||
}
|
||||
}
|
||||
if (dst_fmt->Amask) {
|
||||
DISEMBLE_RGBA(dst, dstbpp, dst_fmt, dstpixel, dstR, dstG,
|
||||
dstB, dstA);
|
||||
} else {
|
||||
DISEMBLE_RGB(dst, dstbpp, dst_fmt, dstpixel, dstR, dstG,
|
||||
dstB);
|
||||
dstA = 0xFF;
|
||||
}
|
||||
|
||||
if (! is_uniform) {
|
||||
TRIANGLE_GET_COLOR
|
||||
modulateR = r;
|
||||
modulateG = g;
|
||||
modulateB = b;
|
||||
modulateA = a;
|
||||
}
|
||||
|
||||
if (flags & SDL_COPY_MODULATE_COLOR) {
|
||||
srcR = (srcR * modulateR) / 255;
|
||||
srcG = (srcG * modulateG) / 255;
|
||||
srcB = (srcB * modulateB) / 255;
|
||||
}
|
||||
if (flags & SDL_COPY_MODULATE_ALPHA) {
|
||||
srcA = (srcA * modulateA) / 255;
|
||||
}
|
||||
if (flags & (SDL_COPY_BLEND | SDL_COPY_ADD)) {
|
||||
/* This goes away if we ever use premultiplied alpha */
|
||||
if (srcA < 255) {
|
||||
srcR = (srcR * srcA) / 255;
|
||||
srcG = (srcG * srcA) / 255;
|
||||
srcB = (srcB * srcA) / 255;
|
||||
}
|
||||
}
|
||||
switch (flags & (SDL_COPY_BLEND | SDL_COPY_ADD | SDL_COPY_MOD | SDL_COPY_MUL)) {
|
||||
case 0:
|
||||
dstR = srcR;
|
||||
dstG = srcG;
|
||||
dstB = srcB;
|
||||
dstA = srcA;
|
||||
break;
|
||||
case SDL_COPY_BLEND:
|
||||
dstR = srcR + ((255 - srcA) * dstR) / 255;
|
||||
dstG = srcG + ((255 - srcA) * dstG) / 255;
|
||||
dstB = srcB + ((255 - srcA) * dstB) / 255;
|
||||
dstA = srcA + ((255 - srcA) * dstA) / 255;
|
||||
break;
|
||||
case SDL_COPY_ADD:
|
||||
dstR = srcR + dstR;
|
||||
if (dstR > 255)
|
||||
dstR = 255;
|
||||
dstG = srcG + dstG;
|
||||
if (dstG > 255)
|
||||
dstG = 255;
|
||||
dstB = srcB + dstB;
|
||||
if (dstB > 255)
|
||||
dstB = 255;
|
||||
break;
|
||||
case SDL_COPY_MOD:
|
||||
dstR = (srcR * dstR) / 255;
|
||||
dstG = (srcG * dstG) / 255;
|
||||
dstB = (srcB * dstB) / 255;
|
||||
break;
|
||||
case SDL_COPY_MUL:
|
||||
dstR = ((srcR * dstR) + (dstR * (255 - srcA))) / 255;
|
||||
if (dstR > 255)
|
||||
dstR = 255;
|
||||
dstG = ((srcG * dstG) + (dstG * (255 - srcA))) / 255;
|
||||
if (dstG > 255)
|
||||
dstG = 255;
|
||||
dstB = ((srcB * dstB) + (dstB * (255 - srcA))) / 255;
|
||||
if (dstB > 255)
|
||||
dstB = 255;
|
||||
dstA = ((srcA * dstA) + (dstA * (255 - srcA))) / 255;
|
||||
if (dstA > 255)
|
||||
dstA = 255;
|
||||
break;
|
||||
}
|
||||
if (dst_fmt->Amask) {
|
||||
ASSEMBLE_RGBA(dst, dstbpp, dst_fmt, dstR, dstG, dstB, dstA);
|
||||
} else {
|
||||
ASSEMBLE_RGB(dst, dstbpp, dst_fmt, dstR, dstG, dstB);
|
||||
}
|
||||
}
|
||||
TRIANGLE_END_LOOP
|
||||
}
|
||||
|
||||
#endif /* SDL_VIDEO_RENDER_SW && !SDL_RENDER_DISABLED */
|
||||
|
||||
/* vi: set ts=4 sw=4 expandtab: */
|
|
@ -0,0 +1,42 @@
|
|||
/*
|
||||
Simple DirectMedia Layer
|
||||
Copyright (C) 1997-2021 Sam Lantinga <slouken@libsdl.org>
|
||||
|
||||
This software is provided 'as-is', without any express or implied
|
||||
warranty. In no event will the authors be held liable for any damages
|
||||
arising from the use of this software.
|
||||
|
||||
Permission is granted to anyone to use this software for any purpose,
|
||||
including commercial applications, and to alter it and redistribute it
|
||||
freely, subject to the following restrictions:
|
||||
|
||||
1. The origin of this software must not be misrepresented; you must not
|
||||
claim that you wrote the original software. If you use this software
|
||||
in a product, an acknowledgment in the product documentation would be
|
||||
appreciated but is not required.
|
||||
2. Altered source versions must be plainly marked as such, and must not be
|
||||
misrepresented as being the original software.
|
||||
3. This notice may not be removed or altered from any source distribution.
|
||||
*/
|
||||
|
||||
#ifndef SDL_triangle_h_
|
||||
#define SDL_triangle_h_
|
||||
|
||||
#include "../../SDL_internal.h"
|
||||
|
||||
extern int SDL_SW_FillTriangle(SDL_Surface *dst,
|
||||
SDL_Point *d0, SDL_Point *d1, SDL_Point *d2,
|
||||
SDL_BlendMode blend, SDL_Color c0, SDL_Color c1, SDL_Color c2);
|
||||
|
||||
extern int SDL_SW_BlitTriangle(
|
||||
SDL_Surface *src,
|
||||
SDL_Point *s0, SDL_Point *s1, SDL_Point *s2,
|
||||
SDL_Surface *dst,
|
||||
SDL_Point *d0, SDL_Point *d1, SDL_Point *d2,
|
||||
SDL_Color c0, SDL_Color c1, SDL_Color c2);
|
||||
|
||||
extern void trianglepoint_2_fixedpoint(SDL_Point *a);
|
||||
|
||||
#endif /* SDL_triangle_h_ */
|
||||
|
||||
/* vi: set ts=4 sw=4 expandtab: */
|
Loading…
Reference in New Issue