diff options
Diffstat (limited to 'third_party/gldc/src/state.c')
| -rw-r--r-- | third_party/gldc/src/state.c | 236 |
1 files changed, 236 insertions, 0 deletions
diff --git a/third_party/gldc/src/state.c b/third_party/gldc/src/state.c new file mode 100644 index 0000000..a9b2a72 --- /dev/null +++ b/third_party/gldc/src/state.c @@ -0,0 +1,236 @@ +#include <stdbool.h> +#include <string.h> +#include <stdio.h> + +#include "private.h" + +GLboolean STATE_DIRTY = GL_TRUE; + +GLboolean DEPTH_TEST_ENABLED = GL_FALSE; +GLboolean DEPTH_MASK_ENABLED = GL_FALSE; + +GLboolean CULLING_ENABLED = GL_FALSE; + +GLboolean FOG_ENABLED = GL_FALSE; +GLboolean ALPHA_TEST_ENABLED = GL_FALSE; + +GLboolean SCISSOR_TEST_ENABLED = GL_FALSE; +GLenum SHADE_MODEL = PVR_SHADE_GOURAUD; + +GLboolean BLEND_ENABLED = GL_FALSE; + +GLboolean TEXTURES_ENABLED = GL_FALSE; +GLboolean AUTOSORT_ENABLED = GL_FALSE; + +static struct { + int x; + int y; + int width; + int height; + GLboolean applied; +} scissor_rect = {0, 0, 640, 480, false}; + +void _glInitContext() { + scissor_rect.x = 0; + scissor_rect.y = 0; + scissor_rect.width = vid_mode->width; + scissor_rect.height = vid_mode->height; +} + +/* Depth Testing */ +void glClearDepth(float depth) { + /* We reverse because using invW means that farther Z == lower number */ + pvr_set_zclip(MIN(1.0f - depth, PVR_MIN_Z)); +} + +void glScissor(int x, int y, int width, int height) { + + if(scissor_rect.x == x && + scissor_rect.y == y && + scissor_rect.width == width && + scissor_rect.height == height) { + return; + } + + scissor_rect.x = x; + scissor_rect.y = y; + scissor_rect.width = width; + scissor_rect.height = height; + scissor_rect.applied = false; + STATE_DIRTY = GL_TRUE; // FIXME: do we need this? + + _glApplyScissor(false); +} + +/* Setup the hardware user clip rectangle. + + The minimum clip rectangle is a 32x32 area which is dependent on the tile + size use by the tile accelerator. The PVR swithes off rendering to tiles + outside or inside the defined rectangle dependant upon the 'clipmode' + bits in the polygon header. + + Clip rectangles therefore must have a size that is some multiple of 32. + + glScissor(0, 0, 32, 32) allows only the 'tile' in the lower left + hand corner of the screen to be modified and glScissor(0, 0, 0, 0) + disallows modification to all 'tiles' on the screen. + + We call this in the following situations: + + - glEnable(GL_SCISSOR_TEST) is called + - glScissor() is called + - After glKosSwapBuffers() + + This ensures that a clip command is added to every vertex list + at the right place, either when enabling the scissor test, or + when the scissor test changes. +*/ +void _glApplyScissor(int force) { + /* Don't do anyting if clipping is disabled */ + if(!SCISSOR_TEST_ENABLED) { + return; + } + + /* Don't apply if we already applied - nothing changed */ + if(scissor_rect.applied && !force) { + return; + } + + PVRTileClipCommand c; + + int miny, maxx, maxy; + + int scissor_width = MAX(MIN(scissor_rect.width, vid_mode->width), 0); + int scissor_height = MAX(MIN(scissor_rect.height, vid_mode->height), 0); + + /* force the origin to the lower left-hand corner of the screen */ + miny = (vid_mode->height - scissor_height) - scissor_rect.y; + maxx = (scissor_width + scissor_rect.x); + maxy = (scissor_height + miny); + + /* load command structure while mapping screen coords to TA tiles */ + c.flags = PVR_CMD_USERCLIP; + c.d1 = c.d2 = c.d3 = 0; + + uint16_t vw = vid_mode->width >> 5; + uint16_t vh = vid_mode->height >> 5; + + c.sx = CLAMP(scissor_rect.x >> 5, 0, vw); + c.sy = CLAMP(miny >> 5, 0, vh); + c.ex = CLAMP((maxx >> 5) - 1, 0, vw); + c.ey = CLAMP((maxy >> 5) - 1, 0, vh); + + aligned_vector_push_back(&OP_LIST.vector, &c, 1); + aligned_vector_push_back(&PT_LIST.vector, &c, 1); + aligned_vector_push_back(&TR_LIST.vector, &c, 1); + + scissor_rect.applied = true; +} + +Viewport VIEWPORT; + +/* Set the GL viewport */ +void glViewport(int x, int y, int width, int height) { + VIEWPORT.hwidth = width * 0.5f; + VIEWPORT.hheight = height * -0.5f; + VIEWPORT.x_plus_hwidth = x + width * 0.5f; + VIEWPORT.y_plus_hheight = y + height * 0.5f; +} + + +void apply_poly_header(PolyHeader* dst, PolyList* activePolyList) { + const TextureObject *tx1 = TEXTURE_ACTIVE; + uint32_t txr_base; + TRACE(); + + int list_type = activePolyList->list_type; + int gen_color_clamp = PVR_CLRCLAMP_DISABLE; + + int gen_culling = CULLING_ENABLED ? PVR_CULLING_CW : PVR_CULLING_SMALL; + int depth_comp = DEPTH_TEST_ENABLED ? PVR_DEPTHCMP_GEQUAL : PVR_DEPTHCMP_ALWAYS; + int depth_write = DEPTH_MASK_ENABLED ? PVR_DEPTHWRITE_ENABLE : PVR_DEPTHWRITE_DISABLE; + + int gen_shading = SHADE_MODEL; + int gen_clip_mode = SCISSOR_TEST_ENABLED ? PVR_USERCLIP_INSIDE : PVR_USERCLIP_DISABLE; + int gen_fog_type = FOG_ENABLED ? PVR_FOG_TABLE : PVR_FOG_DISABLE; + + int gen_alpha = (BLEND_ENABLED || ALPHA_TEST_ENABLED) ? PVR_ALPHA_ENABLE : PVR_ALPHA_DISABLE; + int blend_src = PVR_BLEND_SRCALPHA; + int blend_dst = PVR_BLEND_INVSRCALPHA; + + if (list_type == PVR_LIST_OP_POLY) { + /* Opaque polys are always one/zero */ + blend_src = PVR_BLEND_ONE; + blend_dst = PVR_BLEND_ZERO; + } else if (list_type == PVR_LIST_PT_POLY) { + /* Punch-through polys require fixed blending and depth modes */ + blend_src = PVR_BLEND_SRCALPHA; + blend_dst = PVR_BLEND_INVSRCALPHA; + depth_comp = PVR_DEPTHCMP_LEQUAL; + } else if (list_type == PVR_LIST_TR_POLY && AUTOSORT_ENABLED) { + /* Autosort mode requires this mode for transparent polys */ + depth_comp = PVR_DEPTHCMP_GEQUAL; + } + + int txr_enable, txr_alpha; + if (!TEXTURES_ENABLED || !tx1 || !tx1->data) { + /* Disable all texturing to start with */ + txr_enable = PVR_TEXTURE_DISABLE; + } else { + txr_alpha = (BLEND_ENABLED || ALPHA_TEST_ENABLED) ? PVR_TXRALPHA_ENABLE : PVR_TXRALPHA_DISABLE; + txr_enable = PVR_TEXTURE_ENABLE; + } + + /* The base values for CMD */ + dst->cmd = PVR_CMD_POLYHDR; + dst->cmd |= txr_enable << 3; + /* Force bits 18 and 19 on to switch to 6 triangle strips */ + dst->cmd |= 0xC0000; + + /* Or in the list type, shading type, color and UV formats */ + dst->cmd |= (list_type << PVR_TA_CMD_TYPE_SHIFT) & PVR_TA_CMD_TYPE_MASK; + dst->cmd |= (PVR_CLRFMT_ARGBPACKED << PVR_TA_CMD_CLRFMT_SHIFT) & PVR_TA_CMD_CLRFMT_MASK; + dst->cmd |= (gen_shading << PVR_TA_CMD_SHADE_SHIFT) & PVR_TA_CMD_SHADE_MASK; + dst->cmd |= (PVR_UVFMT_32BIT << PVR_TA_CMD_UVFMT_SHIFT) & PVR_TA_CMD_UVFMT_MASK; + dst->cmd |= (gen_clip_mode << PVR_TA_CMD_USERCLIP_SHIFT) & PVR_TA_CMD_USERCLIP_MASK; + + /* Polygon mode 1 */ + dst->mode1 = (depth_comp << PVR_TA_PM1_DEPTHCMP_SHIFT) & PVR_TA_PM1_DEPTHCMP_MASK; + dst->mode1 |= (gen_culling << PVR_TA_PM1_CULLING_SHIFT) & PVR_TA_PM1_CULLING_MASK; + dst->mode1 |= (depth_write << PVR_TA_PM1_DEPTHWRITE_SHIFT) & PVR_TA_PM1_DEPTHWRITE_MASK; + dst->mode1 |= (txr_enable << PVR_TA_PM1_TXRENABLE_SHIFT) & PVR_TA_PM1_TXRENABLE_MASK; + + /* Polygon mode 2 */ + dst->mode2 = (blend_src << PVR_TA_PM2_SRCBLEND_SHIFT) & PVR_TA_PM2_SRCBLEND_MASK; + dst->mode2 |= (blend_dst << PVR_TA_PM2_DSTBLEND_SHIFT) & PVR_TA_PM2_DSTBLEND_MASK; + dst->mode2 |= (gen_fog_type << PVR_TA_PM2_FOG_SHIFT) & PVR_TA_PM2_FOG_MASK; + dst->mode2 |= (gen_color_clamp << PVR_TA_PM2_CLAMP_SHIFT) & PVR_TA_PM2_CLAMP_MASK; + dst->mode2 |= (gen_alpha << PVR_TA_PM2_ALPHA_SHIFT) & PVR_TA_PM2_ALPHA_MASK; + + if (txr_enable == PVR_TEXTURE_DISABLE) { + dst->mode3 = 0; + } else { + GLuint filter = PVR_FILTER_NEAREST; + if (tx1->minFilter == GL_LINEAR && tx1->magFilter == GL_LINEAR) filter = PVR_FILTER_BILINEAR; + + dst->mode2 |= (txr_alpha << PVR_TA_PM2_TXRALPHA_SHIFT) & PVR_TA_PM2_TXRALPHA_MASK; + dst->mode2 |= (filter << PVR_TA_PM2_FILTER_SHIFT) & PVR_TA_PM2_FILTER_MASK; + dst->mode2 |= (tx1->mipmap_bias << PVR_TA_PM2_MIPBIAS_SHIFT) & PVR_TA_PM2_MIPBIAS_MASK; + dst->mode2 |= (PVR_TXRENV_MODULATEALPHA << PVR_TA_PM2_TXRENV_SHIFT) & PVR_TA_PM2_TXRENV_MASK; + + dst->mode2 |= (DimensionFlag(tx1->width) << PVR_TA_PM2_USIZE_SHIFT) & PVR_TA_PM2_USIZE_MASK; + dst->mode2 |= (DimensionFlag(tx1->height) << PVR_TA_PM2_VSIZE_SHIFT) & PVR_TA_PM2_VSIZE_MASK; + + /* Polygon mode 3 */ + dst->mode3 = (GL_FALSE << PVR_TA_PM3_MIPMAP_SHIFT) & PVR_TA_PM3_MIPMAP_MASK; + dst->mode3 |= (tx1->color << PVR_TA_PM3_TXRFMT_SHIFT) & PVR_TA_PM3_TXRFMT_MASK; + + /* Convert the texture address */ + txr_base = (uint32_t)tx1->data; + txr_base = (txr_base & 0x00fffff8) >> 3; + dst->mode3 |= txr_base; + } + + dst->d1 = dst->d2 = 0xffffffff; + dst->d3 = dst->d4 = 0xffffffff; +} |