Dengine/src/Renderer.c
Doyle Thai 46629a489a Add debug rendering, fix misaligned pos render bug
Rendering using a non-default quad specifies normalised coordinates
relative to the frame buffer size. Hence each render of these frames
should origin from (0,0) any other value is invalid.
2016-07-08 02:45:37 +10:00

216 lines
7.0 KiB
C

#include "Dengine/Platform.h"
#include "Dengine/OpenGL.h"
#include "Dengine/Renderer.h"
#define RENDER_BOUNDING_BOX FALSE
DebugRenderer debugRenderer = {0};
INTERNAL void updateBufferObject(Renderer *const renderer,
RenderQuad *const quads, const i32 numQuads)
{
// TODO(doyle): We assume that vbo and vao are assigned
const i32 numVertexesInQuad = 4;
renderer->numVertexesInVbo = numQuads * numVertexesInQuad;
glBindBuffer(GL_ARRAY_BUFFER, renderer->vbo);
glBufferData(GL_ARRAY_BUFFER, numQuads * sizeof(RenderQuad), quads,
GL_STREAM_DRAW);
glBindBuffer(GL_ARRAY_BUFFER, 0);
}
#if 0
void renderer_backgroundTiles(Renderer *const renderer, const v2 tileSize,
World *const world, TexAtlas *const atlas,
Texture *const tex)
{
RenderQuad worldQuads[ARRAY_COUNT(world->tiles)] = {0};
i32 quadIndex = 0;
for (i32 i = 0; i < ARRAY_COUNT(world->tiles); i++)
{
Tile tile = world->tiles[i];
v2 tilePosInPixel = v2_scale(tile.pos, tileSize.x);
if ((tilePosInPixel.x < renderer->size.w && tilePosInPixel.x >= 0) &&
(tilePosInPixel.y < renderer->size.h && tilePosInPixel.y >= 0))
{
const v4 texRect = atlas->texRect[terraincoords_ground];
const v4 tileRect = getRect(tilePosInPixel, tileSize);
RenderQuad tileQuad =
renderer_createQuad(renderer, tileRect, texRect, tex);
worldQuads[quadIndex++] = tileQuad;
}
}
updateBufferObject(renderer, worldQuads, quadIndex);
renderer_object(renderer, V2(0.0f, 0.0f), renderer->size, 0.0f,
V3(0, 0, 0), tex);
}
#endif
void renderer_string(Renderer *const renderer, Font *const font,
const char *const string, v2 pos, f32 rotate,
v3 color)
{
i32 quadIndex = 0;
i32 strLen = common_strlen(string);
RenderQuad *stringQuads = CAST(RenderQuad *)calloc(strLen, sizeof(RenderQuad));
f32 baseline = pos.y;
for (i32 i = 0; i < strLen; i++)
{
// NOTE(doyle): Atlas packs fonts tightly, so offset the codepoint to
// its actual atlas index, i.e. we skip the first 31 glyphs
i32 codepoint = string[i];
i32 relativeIndex = codepoint - font->codepointRange.x;
CharMetrics charMetric = font->charMetrics[relativeIndex];
pos.y = baseline - charMetric.offset.y;
const v4 charRectOnScreen = getRect(
pos, V2(CAST(f32) font->maxSize.w, CAST(f32) font->maxSize.h));
pos.x += charMetric.advance;
/* Get texture out */
v4 charTexRect = font->atlas->texRect[relativeIndex];
renderer_flipTexCoord(&charTexRect, FALSE, TRUE);
RenderQuad charQuad = renderer_createQuad(renderer, charRectOnScreen,
charTexRect, font->tex);
stringQuads[quadIndex++] = charQuad;
}
// NOTE(doyle): We render at the renderer's size because we create quads
// relative to the window size, hence we also render at the origin since
// we're rendering a window sized buffer
updateBufferObject(renderer, stringQuads, quadIndex);
renderer_object(renderer, V2(0.0f, 0.0f), renderer->size, rotate, color,
font->tex);
free(stringQuads);
}
void renderer_debugString(Renderer *const renderer, Font *const font,
const char *const string)
{
/* Intialise debug object */
if (!debugRenderer.init)
{
debugRenderer.stringPos =
V2(0.0f, renderer->size.y -
(1.8f * asset_getVFontSpacing(font->metrics)));
debugRenderer.init = TRUE;
}
f32 rotate = 0;
v3 color = V3(0, 0, 0);
renderer_string(renderer, font, string, debugRenderer.stringPos, rotate,
color);
debugRenderer.stringPos.y -= (0.9f * asset_getVFontSpacing(font->metrics));
}
void renderer_entity(Renderer *renderer, Entity *entity, f32 dt, f32 rotate,
v3 color)
{
SpriteAnim *anim = &entity->anim[entity->currAnimIndex];
v4 texRect = anim->rect[anim->currRectIndex];
anim->currDuration -= dt;
if (anim->currDuration <= 0.0f)
{
anim->currRectIndex++;
anim->currRectIndex = anim->currRectIndex % anim->numRects;
texRect = anim->rect[anim->currRectIndex];
anim->currDuration = anim->duration;
}
if (entity->direction == direction_east)
{
// NOTE(doyle): Flip the x coordinates to flip the tex
renderer_flipTexCoord(&texRect, TRUE, FALSE);
}
RenderQuad entityQuad =
renderer_createDefaultQuad(renderer, texRect, entity->tex);
updateBufferObject(renderer, &entityQuad, 1);
renderer_object(renderer, entity->pos, entity->size, rotate, color,
entity->tex);
}
void renderer_object(Renderer *renderer, v2 pos, v2 size, f32 rotate, v3 color,
Texture *tex)
{
shader_use(renderer->shader);
mat4 transMatrix = mat4_translate(pos.x, pos.y, 0.0f);
mat4 rotateMatrix = mat4_rotate(rotate, 0.0f, 0.0f, 1.0f);
// NOTE(doyle): We draw everything as a unit square in OGL. Scale it to size
// TODO(doyle): We should have a notion of hitbox size and texture size
// we're going to render so we can draw textures that may be bigger than the
// entity, (slightly) but keep a consistent bounding box
mat4 scaleMatrix = mat4_scale(size.x, size.y, 1.0f);
mat4 model = mat4_mul(transMatrix, mat4_mul(rotateMatrix, scaleMatrix));
//mat4 model = mat4_mul(transMatrix, rotateMatrix);
shader_uniformSetMat4fv(renderer->shader, "model", model);
glCheckError();
// TODO(doyle): Unimplemented
// this->shader->uniformSetVec3f("spriteColor", color);
#if RENDER_BOUNDING_BOX
glBindVertexArray(renderer->vao);
glDrawArrays(GL_TRIANGLE_STRIP, 0, renderer->numVertexesInVbo);
glBindVertexArray(0);
#endif
glActiveTexture(GL_TEXTURE0);
if (tex)
{
glBindTexture(GL_TEXTURE_2D, tex->id);
shader_uniformSet1i(renderer->shader, "tex", 0);
}
glBindVertexArray(renderer->vao);
glDrawArrays(GL_TRIANGLE_STRIP, 0, renderer->numVertexesInVbo);
glBindVertexArray(0);
glBindTexture(GL_TEXTURE_2D, 0);
glCheckError();
}
RenderQuad renderer_createQuad(Renderer *renderer, v4 quadRect, v4 texRect,
Texture *tex)
{
// NOTE(doyle): Draws a series of triangles (three-sided polygons) using
// vertices v0, v1, v2, then v2, v1, v3 (note the order)
RenderQuad result = {0};
v4 quadRectNdc = quadRect;
quadRectNdc.e[0] *= renderer->vertexNdcFactor.w;
quadRectNdc.e[1] *= renderer->vertexNdcFactor.h;
quadRectNdc.e[2] *= renderer->vertexNdcFactor.w;
quadRectNdc.e[3] *= renderer->vertexNdcFactor.h;
v2 texNdcFactor = V2(1.0f / tex->width, 1.0f / tex->height);
v4 texRectNdc = texRect;
texRectNdc.e[0] *= texNdcFactor.w;
texRectNdc.e[1] *= texNdcFactor.h;
texRectNdc.e[2] *= texNdcFactor.w;
texRectNdc.e[3] *= texNdcFactor.h;
result.vertex[0] = V4(quadRectNdc.x, quadRectNdc.y, texRectNdc.x,
texRectNdc.y); // Top left
result.vertex[1] = V4(quadRectNdc.x, quadRectNdc.w, texRectNdc.x,
texRectNdc.w); // Bottom left
result.vertex[2] = V4(quadRectNdc.z, quadRectNdc.y, texRectNdc.z,
texRectNdc.y); // Top right
result.vertex[3] = V4(quadRectNdc.z, quadRectNdc.w, texRectNdc.z,
texRectNdc.w); // Bottom right
return result;
}